Steamrollered by PC compatibles obviously. At the time it wasn't clear yet that for 8086/8 you needed register level hardware compatibility, not just BIOS call compatibility (as in the CP/M days) to stay in the market. And nonstandard disk format to boot.
The non-standard floppy format was a huge annoyance for users. While the higher density formats were cool, the hardware could operate on PC-compatible format, but the OS wouldn’t support it.
ROM BIOS compatibility would have been nice, but it could be implemented at the custom MS-DOS version and run from RAM, but I’m not sure there were clean room implementations back at that point.
